package common

/*
 * This file is part of Autogits.
 *
 * Copyright © 2024 SUSE LLC
 *
 * Autogits is free software: you can redistribute it and/or modify it under
 * the terms of the GNU General Public License as published by the Free Software
 * Foundation, either version 2 of the License, or (at your option) any later
 * version.
 *
 * Autogits is distributed in the hope that it will be useful, but WITHOUT ANY
 * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
 * PARTICULAR PURPOSE. See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * Foobar. If not, see <https://www.gnu.org/licenses/>.
 */

import (
	"encoding/json"
	"fmt"
	"io"
	"log"
	"os"
	"slices"
	"strings"
)

type ConfigFile struct {
	GitProjectName []string
}

func ReadConfig(reader io.Reader) (*ConfigFile, error) {
	data, err := io.ReadAll(reader)
	if err != nil {
		return nil, fmt.Errorf("Error reading config data: %w", err)
	}

	config := ConfigFile{}
	if err := json.Unmarshal(data, &config.GitProjectName); err != nil {
		return nil, fmt.Errorf("Error parsing Git Project paths: %w", err)
	}

	return &config, nil
}

func ReadConfigFile(filename string) (*ConfigFile, error) {
	file, err := os.Open(filename)
	if err != nil {
		return nil, fmt.Errorf("Cannot open config file for reading. err: %w", err)
	}
	defer file.Close()

	return ReadConfig(file)
}

func ReadWorkflowConfig(gitea Gitea, git_project string) (*AutogitConfig, error) {
	hash := strings.Split(git_project, "#")
	branch := ""
	if len(hash) > 1 {
		branch = hash[1]
	}

	a := strings.Split(hash[0], "/")
	prjGitRepo := DefaultGitPrj
	switch len(a) {
	case 1:
	case 2:
		prjGitRepo = a[1]
	default:
		return nil, fmt.Errorf("Missing org/repo in projectgit: %s", git_project)
	}

	data, _, err := gitea.GetRepositoryFileContent(a[0], prjGitRepo, branch, "workflow.config")
	if err != nil {
		return nil, fmt.Errorf("Error fetching 'workflow.config': %w", err)
	}

	var config AutogitConfig
	if err := json.Unmarshal(data, &config); err != nil {
		return nil, fmt.Errorf("Error parsing config file: %w", err)
	}

	config.GitProjectName = a[0] + "/" + prjGitRepo
	if len(branch) > 0 {
		config.GitProjectName = config.GitProjectName + "#" + branch
	}
	if len(config.Organization) < 1 {
		config.Organization = a[0]
	}
	log.Println(config)
	return &config, nil
}

func ResolveWorkflowConfigs(gitea Gitea, config *ConfigFile) ([]*AutogitConfig, error) {
	configs := make([]*AutogitConfig, 0, len(config.GitProjectName))
	for _, git_project := range config.GitProjectName {
		c, err := ReadWorkflowConfig(gitea, git_project)
		if err != nil {
			// can't sync, so ignore for now
			log.Println(err)
		} else {
			configs = append(configs, c)
		}
	}

	return configs, nil
}

type AutogitConfig struct {
	Workflows      []string // [pr, direct, test]
	Organization   string
	GitProjectName string   // Organization/GitProjectName.git is PrjGit
	Branch         string   // branch name of PkgGit that aligns with PrjGit submodules
	Reviewers      []string // only used by `pr` workflow
}

type AutogitConfigs []*AutogitConfig

func (configs AutogitConfigs) GetPrjGitConfig(org, repo, branch string) *AutogitConfig {
	for _, c := range configs {
		if c.Organization == org && c.Branch == branch {
			return c
		}
	}

	return nil
}

func ReadWorkflowConfigs(reader io.Reader) ([]*AutogitConfig, error) {
	data, err := io.ReadAll(reader)
	if err != nil {
		return nil, fmt.Errorf("Error reading config file. err: %w", err)
	}

	var config []*AutogitConfig
	if err = json.Unmarshal(data, &config); err != nil {
		return nil, fmt.Errorf("Error parsing config file. err: %w", err)
	}

	availableWorkflows := []string{"pr", "direct", "test"}
	for _, workflow := range config {
		pr := false
		for _, w := range workflow.Workflows {
			if w == "pr" {
				pr = true
			}
			if !slices.Contains(availableWorkflows, w) {
				return nil, fmt.Errorf(
					"Invalid Workflow '%s'. Only available workflows are: %s",
					w, strings.Join(availableWorkflows, " "),
				)
			}
		}
		if len(workflow.GitProjectName) == 0 {
			workflow.GitProjectName = DefaultGitPrj
		}
		if !pr && len(workflow.Reviewers) > 0 {
			log.Println(" Warning: non-PR-only workflows contains Reviewers. These are ignored in Org:", workflow.Organization)
		}
	}

	return config, nil
}

func ReadWorkflowConfigsFile(filename string) ([]*AutogitConfig, error) {
	file, err := os.Open(filename)
	if err != nil {
		return nil, fmt.Errorf("Cannot open config file for reading. err: %w", err)
	}
	defer file.Close()

	return ReadWorkflowConfigs(file)
}